DY does not have interline ticketing agreements. Rebooking OA is simply not in the cards.
At this point, I would either:
1. Wait and do nothing for a few days. If it turns out that the software fix implemented by Boeing is the source of the issue (if there is an issue at all) and the "ban" is lifted, perhaps your flight will be reinstated and you will fly as scheduled (if you wish).
2. Cancel for a full refund and purchase a new ticket on a new routing. Triple check that your flight interruption insurance covers the fare difference.
The two are not mutually exclusive and it may well be that you don't want to fly DY in any event or the MAX makes you queasy even if not grounded. On the other hand, the passage of time won't make tickets routed NYC-SNN cheaper or easier to find.